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Commitments and contingencies - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011
Commitments and Contingencies [Line Items] |  |
Rent expense | $ 650,000 | $ 601,000
Remediation costs | 102,000 | 86,000
Officers' compensation | 288,500 |
Insurance policy, amount | $ 1,000,000 |

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- Details
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- Definition Insurance Policy Amount + References No definition available. + Details
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- Definition Remediation Costs Incurred + References No definition available. + Details
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- Definition Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses. + References No definition available. + Details
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- Definition Expenditures for salaries of officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense or other labor-related non-salary expense. For commercial and industrial companies, excludes any direct and overhead labor that is included in cost of goods sold. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.4) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 + Details
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